The short version
Sea to Summit Ultra-Sil is the lightest quality dry sack available. We researched submersion waterproofing and compared it to Aqua-Quest bags at the same capacity.
Who it's for
Buy this if: Every backpacker who carries a sleeping bag or critical dry gear.
Skip this if: No one — sleeping bag protection is non-negotiable.
In practice
Critical Gear Protection
A wet sleeping bag at 3,000 feet in a rainstorm is a survival problem. The sleeping bag is the single piece of gear that cannot get wet. A 0.88 oz sack providing a submersion-rated waterproof barrier around your sleeping bag is the best weight-to-protection investment in a backpack.
What we loved
+ 0.88 oz for a 4L sack — adds negligible weight+ 10,000mm rating provides full submersion protection+ Roll-top buckle is faster and more secure than twist-and-fold systems
What we'd change
– Silnylon is puncture-susceptible — inspect before each trip– Not a floating dry bag — will sink if dropped in current
Where to buy
Check the current price
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